The use of ultrasonic instruments in surgical applications is well known. One widely used type of instrument is an ultrasonic handpiece that is used in opthalmological applications, such as in the removal of cataracts from the eye. A typical instrument uses a magnetostrictive transducer formed by a stack of laminations surrounded by a coil of wire to which alternating current energy is applied. The stack of laminations converts the electrical energy to mechanical vibratory energy. A work tip is at the distal end of the handpiece that is connected to the transducer by a connecting body. The mechanical vibratory energy produced by the transducer is conveyed to the distal end of the work tip and this energy is applied close to or against a piece of tissue that is emulsified by the vibratory energy.
Such a handpiece usually utilizes a source of aspiration flow force so that the emulsified tissue can be removed from the operating site. The aspiration force can be provided by, for example, a peristaltic type suction pump and there is a fluid connection between the pump and the work tip, usually through a central aspiration passage formed in the work tip that is in communication with the aspiration force pump through a conduit that is connected to a fitting on the handpiece that is in communication with the tip central passage. The aspiration flow force passage also can extend through the connecting body. Hand pieces of this type can also have a sleeve, or cocoon, that surrounds and is spaced from the work tip to form a passage through which an irrigation fluid is supplied from an external source. The irrigation fluid exits from this passage at or near the distal end of the tip to supply the irrigation fluid to the operating site.
After each use, the complete handpiece can be sterilized, such as by a conventional gas sterilization technique, or the work tip alone can be immersed in a liquid sterilizing solution. In instruments of this type there often is a threaded connection between the proximal end of the work tip and the connecting body. The threaded connection is relatively permanent in the sense that it is broken only when the work tip has to be replaced, this occurring after many uses of the handpiece.
A need exists to provide an ultrasonic handpiece of the forgoing type in which the work tip would be used for only a single use and then disposed of. This can have a desired advantage of eliminating the need for sterilization of the handpiece, or making sterilization easier, and making conditions for use of the instrument more sanitary from one patient to the next. However, if the work tip is to be made for single use, it becomes necessary to provide an arrangement by which the tip can be easily changed and the aspiration and irrigation flow passages can be easily and reliably established.